In fabrication of spaced, bumped component structures it is often necessary to control the gap size independent of the solder ball size. For example, in one pressure sensor application an integrated circuit chip is flip-chip bump bonded to a substrate. The facing surfaces of the chip and substrate may typically be metallized. A hole or recess in the other side of the substrate creates a diaphragm structure beneath the metallized surface so movement of the diaphragm due to gas or fluid pressure can be sensed by changes in capacitance between the metallized surfaces due to changes in the size of the gap between them. It is also possible to provide a diaphragm layer without the use of the said hole or recess. In such an application it is desirable to have a gap that is relatively small so that very small movements of the diaphragm may be readily detected. But typically the gap size is defined by the size or diameter of the solder bumps and the bumps are generally no smaller than 80-120 μms. This is so because generally the chip and the substrate have different coefficients of thermal expansion (CTE) e.g., chip is silicon (3-5 ppm/deg C.); substrate is alumina (6-8 ppm/deg C.). The stresses that occur during temperature cycling typically require a solder bump size greater than approximately 80-120 μms. This is but one illustration of the need to control the gap size independent of bump size. In other cases there may be no difference in CTE but the desired gap size may be larger or smaller than the bump size. Another problem with controlling gap size relates to tolerance. That is, solder bumps of 80-120 μms, for example, typically have a manufacturing tolerance of ±15 μm; not an acceptable condition when gap size and small variations in gap size are used to sense diaphragm movement, for example.